Since its introduction, the scanning tunneling microscope (STM) (1,2) has been used mainly to determine surface topography and structure at the atomic level. However, there have also been several reports of its use in vacuum or air for surface modification and submicron lithography (3-8). A recent paper from this laboratory (9) described a similar technique, based on the scanning electrochemical microscope (SECM) (10), for the high resolution etching of semiconductors immersed in a liquid. The present invention involves new uses of a modified STM both to deposit extremely fine patterns of metals, semiconductors or polymers in polymer films and to etch the conducting substrate with very high resolution.